xputimage.c

早期freebsd实现

/* 2Lm */ { s   s   s   S   R   W   s   n   w   S   S   S },
/* 4Lm */ { l   l   l   L   W   R   l   w   n   L   L   L },
/* 1Ll */ { R   R   R   n   s   l   R   S   L   n   n   n },
/* 2Ll */ { R   R   R   n   s   l   R   S   L   n   n   n },
/* 4Ll */ { R   R   R   n   s   l   R   S   L   n   n   n }

#undef n
#undef s
#undef l
#undef w
#undef R
#undef S
#undef L
#undef W

};

/* Of course, the table above is a lie.  We also need to factor in the
 * order of the source data to cope with swapping half of a unit at the
 * end of a scanline, since we are trying to avoid de-ref'ing off the
 * end of the source.
 *
 * Defines whether the first half of a unit has the first half of the data
 */
static int Const HalfOrder[12] = {
	LSBFirst, /* 1Mm */
	LSBFirst, /* 2Mm */
	LSBFirst, /* 4Mm */
	LSBFirst, /* 1Ml */
	MSBFirst, /* 2Ml */
	MSBFirst, /* 4Ml */
	LSBFirst, /* 1Lm */
	MSBFirst, /* 2Lm */
	MSBFirst, /* 4Lm */
	LSBFirst, /* 1Ll */
	LSBFirst, /* 2Ll */
	LSBFirst  /* 4Ll */
	};

/* Finally, for SwapWords cases, the half order depends not just on the source
 * but also on the destination scanline unit.  Use of this table changes some
 * MSBFirsts to LSBFirsts that are "do not care" (because the function will be
 * NoSwap or SwapBits) in addition to changing the desired ones.
 */

static int Const HalfOrderWord[12] = {
	MSBFirst, /* 1Mm */
	MSBFirst, /* 2Mm */
	MSBFirst, /* 4Mm */
	MSBFirst, /* 1Ml */
	MSBFirst, /* 2Ml */
	LSBFirst, /* 4Ml */
	MSBFirst, /* 1Lm */
	MSBFirst, /* 2Lm */
	LSBFirst, /* 4Lm */
	MSBFirst, /* 1Ll */
	MSBFirst, /* 2Ll */
	MSBFirst  /* 4Ll */
	};

/*
 * This macro creates a value from 0 to 11 suitable for indexing
 * into the table above.
 */
#define	ComposeIndex(bitmap_unit, bitmap_bit_order, byte_order)			\
		(((bitmap_unit == 32) ? 2 : ((bitmap_unit == 16) ? 1 : 0))	\
		     + (((bitmap_bit_order == MSBFirst) ? 0 : 3)		\
		     + ((byte_order == MSBFirst) ? 0 : 6)))

/* Cancel a GetReq operation, before doing _XSend or Data */

#if __STDC__ && !(defined(UNIXCPP))
#define UnGetReq(name)\
    dpy->bufptr -= SIZEOF(x##name##Req);\
    dpy->request--
#else
#define UnGetReq(name)\
    dpy->bufptr -= SIZEOF(x/**/name/**/Req);\
    dpy->request--
#endif

static void
SendXYImage(dpy, req, image, req_xoffset, req_yoffset)
    register Display *dpy;
    register xPutImageReq *req;
    register XImage *image;
    int req_xoffset, req_yoffset;
{
    register int j;
    long total_xoffset, bytes_per_src, bytes_per_dest, length;
    long bytes_per_line, bytes_per_src_plane, bytes_per_dest_plane;
    char *src, *dest, *buf;
    char *extra = (char *)NULL;
    register int (*swapfunc)();
    int half_order;

    total_xoffset = image->xoffset + req_xoffset;
    req->leftPad = total_xoffset & (dpy->bitmap_unit - 1);
    total_xoffset = (unsigned)(total_xoffset - req->leftPad) >> 3;
    /* The protocol requires left-pad of zero on all ZPixmap, even
     * though the 1-bit case is identical to bitmap format.  This is a
     * bug in the protocol, caused because 1-bit ZPixmap was added late
     * in the game.  Hairy shifting code compensation isn't worth it,
     * just use XYPixmap format instead.
     */
    if ((req->leftPad != 0) && (req->format == ZPixmap))
	req->format = XYPixmap;
    bytes_per_dest = (unsigned long)ROUNDUP((long)req->width + req->leftPad,
					    dpy->bitmap_pad) >> 3;
    bytes_per_dest_plane = bytes_per_dest * req->height;
    length = bytes_per_dest_plane * image->depth;
    req->length += (length + 3) >> 2;

    swapfunc = SwapFunction[ComposeIndex(image->bitmap_unit,
					 image->bitmap_bit_order,
					 image->byte_order)]
			   [ComposeIndex(dpy->bitmap_unit,
					 dpy->bitmap_bit_order,
					 dpy->byte_order)];
    half_order = HalfOrder[ComposeIndex(image->bitmap_unit,
					image->bitmap_bit_order,
					image->byte_order)];
    if (half_order == MSBFirst)
	half_order = HalfOrderWord[ComposeIndex(dpy->bitmap_unit,
						dpy->bitmap_bit_order,
						dpy->byte_order)];

    src = image->data + (image->bytes_per_line * req_yoffset) + total_xoffset;

    /* when total_xoffset > 0, we have to worry about stepping off the
     * end of image->data.
     */
    if ((swapfunc == NoSwap) &&
	(image->bytes_per_line == bytes_per_dest) &&
	(((total_xoffset == 0) &&
	  ((image->depth == 1) || (image->height == req->height))) ||
	 ((image->depth == 1) &&
	  ((req_yoffset + req->height) < (unsigned)image->height)))) {
	Data(dpy, src, length);
	return;
    }

    length = ROUNDUP(length, 4);
    if ((dpy->bufptr + length) > dpy->bufmax) {
	if ((buf = _XAllocScratch(dpy, (unsigned long) (length))) == NULL) {
	    UnGetReq(PutImage);
	    return;	
	}
    }
    else
	buf = dpy->bufptr;

    bytes_per_src = (req->width + req->leftPad + (unsigned)7) >> 3;
    bytes_per_line = image->bytes_per_line;
    bytes_per_src_plane = bytes_per_line * image->height;
    total_xoffset &= (image->bitmap_unit - 1) >> 3;

    if ((total_xoffset > 0) &&
	(image->byte_order != image->bitmap_bit_order)) {
	char *temp;
	long bytes_per_temp_plane, temp_length;

	bytes_per_line = bytes_per_src + total_xoffset;
	src -= total_xoffset;
	bytes_per_temp_plane = bytes_per_line * req->height;
	temp_length = ROUNDUP(bytes_per_temp_plane * image->depth, 4);
	if (buf == dpy->bufptr) {
	    if (! (temp = _XAllocScratch(dpy, (unsigned long) temp_length))) {
		UnGetReq(PutImage);
		return;
	    }
	}
	else
	    if ((extra = temp = Xmalloc((unsigned) temp_length)) == NULL) {
		UnGetReq(PutImage);
		return;
	    }

	swapfunc = SwapFunction[ComposeIndex(image->bitmap_unit,
					     image->bitmap_bit_order,
					     image->byte_order)]
			       [ComposeIndex(image->bitmap_unit,
					     dpy->byte_order,
					     dpy->byte_order)];
	for (dest = temp, j = image->depth;
	     --j >= 0;
	     src += bytes_per_src_plane, dest += bytes_per_temp_plane)
	    (*swapfunc)((unsigned char *)src, (unsigned char *)dest,
			bytes_per_line, (long)image->bytes_per_line,
			bytes_per_line, req->height, half_order);
	swapfunc = SwapFunction[ComposeIndex(image->bitmap_unit,
					     dpy->byte_order,
					     dpy->byte_order)]
			       [ComposeIndex(dpy->bitmap_unit,
					     dpy->bitmap_bit_order,
					     dpy->byte_order)];
	half_order = HalfOrder[ComposeIndex(image->bitmap_unit,
					    dpy->byte_order,
					    dpy->byte_order)];
	src = temp + total_xoffset;
	bytes_per_src_plane = bytes_per_temp_plane;
    }

    for (dest = buf, j = image->depth;
	 --j >= 0;
	 src += bytes_per_src_plane, dest += bytes_per_dest_plane)
	(*swapfunc)((unsigned char *)src, (unsigned char *)dest,
		    bytes_per_src, bytes_per_line,
		    bytes_per_dest, req->height, half_order);

    if (extra)
	Xfree(extra);

    if (buf == dpy->bufptr)
	dpy->bufptr += length;
    else
	_XSend(dpy, buf, length);
  }

static void
SendZImage(dpy, req, image, req_xoffset, req_yoffset,
	   dest_bits_per_pixel, dest_scanline_pad)
    register Display *dpy;
    register xPutImageReq *req;
    register XImage *image;
    int req_xoffset, req_yoffset, dest_bits_per_pixel, dest_scanline_pad;
{
    long bytes_per_src, bytes_per_dest, length;
    unsigned char *src, *dest;
    unsigned char *shifted_src = NULL;

    req->leftPad = 0;
    bytes_per_src = ROUNDUP((long)req->width * image->bits_per_pixel, 8) >> 3;
    bytes_per_dest = ROUNDUP((long)req->width * dest_bits_per_pixel,
			     dest_scanline_pad) >> 3;
    length = bytes_per_dest * req->height;
    req->length += (length + 3) >> 2;

    src = (unsigned char *)image->data +
	  (req_yoffset * image->bytes_per_line) +
	  ((req_xoffset * image->bits_per_pixel) >> 3);
    if ((image->bits_per_pixel == 4) && ((unsigned int) req_xoffset & 0x01)) {
	if (! (shifted_src = (unsigned char *)
	       Xmalloc((unsigned) (req->height * image->bytes_per_line)))) {
	    UnGetReq(PutImage);
	    return;
	}

	ShiftNibblesLeft(src, shifted_src, bytes_per_src,
			 (long) image->bytes_per_line,
			 (long) image->bytes_per_line, req->height,
			 image->byte_order);
	src = shifted_src;
    }

    /* when req_xoffset > 0, we have to worry about stepping off the
     * end of image->data.
     */
    if (((image->byte_order == dpy->byte_order) ||
	 (image->bits_per_pixel == 8)) &&
	((long)image->bytes_per_line == bytes_per_dest) &&
	((req_xoffset == 0) ||
	 ((req_yoffset + req->height) < (unsigned)image->height))) {
	Data(dpy, (char *)src, length);
	if (shifted_src)
	    Xfree((char *)shifted_src);
	return;
    }

    length = ROUNDUP(length, 4);
    if ((dpy->bufptr + length) <= dpy->bufmax)
	dest = (unsigned char *)dpy->bufptr;
    else
	if ((dest = (unsigned char *)
	     _XAllocScratch(dpy, (unsigned long)(length))) == NULL) {
	    if (shifted_src) Xfree((char *) shifted_src);
	    UnGetReq(PutImage);
	    return;
	}

    if ((image->byte_order == dpy->byte_order) ||
	(image->bits_per_pixel == 8))
	NoSwap(src, dest, bytes_per_src, (long)image->bytes_per_line,
	       bytes_per_dest, req->height, image->byte_order);
    else if (image->bits_per_pixel == 32)
	SwapFourBytes(src, dest, bytes_per_src, (long)image->bytes_per_line,
		      bytes_per_dest, req->height, image->byte_order);
    else if (image->bits_per_pixel == 24)
	SwapThreeBytes(src, dest, bytes_per_src, (long)image->bytes_per_line,
		       bytes_per_dest, req->height, image->byte_order);
    else if (image->bits_per_pixel == 16)
	SwapTwoBytes(src, dest, bytes_per_src, (long)image->bytes_per_line,
		     bytes_per_dest, req->height, image->byte_order);
    else
	SwapNibbles(src, dest, bytes_per_src, (long)image->bytes_per_line,
		    bytes_per_dest, req->height);

    if (dest == (unsigned char *)dpy->bufptr)
	dpy->bufptr += length;
    else
	_XSend(dpy, (char *)dest, length);

    if (shifted_src)
        Xfree((char *)shifted_src);
}

static void
PutImageRequest(dpy, d, gc, image, req_xoffset, req_yoffset, x, y,
		req_width, req_height, dest_bits_per_pixel, dest_scanline_pad)
    register Display *dpy;
    Drawable d;
    GC gc;
    register XImage *image;
    int x, y;
    unsigned int req_width, req_height;
    int req_xoffset, req_yoffset, dest_bits_per_pixel, dest_scanline_pad;
{
    register xPutImageReq *req;

    GetReq(PutImage, req);
    req->drawable = d;
    req->gc = gc->gid;
    req->dstX = x;
    req->dstY = y;
    req->width = req_width;
    req->height = req_height;
    req->depth = image->depth;
    req->format = image->format;
    if ((image->depth == 1) || (image->format != ZPixmap))
	SendXYImage(dpy, req, image, req_xoffset, req_yoffset);
    else
	SendZImage(dpy, req, image, req_xoffset, req_yoffset,
		   dest_bits_per_pixel, dest_scanline_pad);
}
	
static void
PutSubImage (dpy, d, gc, image, req_xoffset, req_yoffset, x, y,
	     req_width, req_height, dest_bits_per_pixel, dest_scanline_pad)
    register Display *dpy;
    Drawable d;
    GC gc;
    register XImage *image;
    int x, y;
    unsigned int req_width, req_height;
    int req_xoffset, req_yoffset, dest_bits_per_pixel, dest_scanline_pad;

{
    int left_pad, BytesPerRow, Available;

    if ((req_width == 0) || (req_height == 0))
	return;
    
    Available = ((65536 < dpy->max_request_size) ? (65536 << 2)
						 : (dpy->max_request_size << 2))
		- SIZEOF(xPutImageReq);

    if ((image->depth == 1) || (image->format != ZPixmap)) {
	left_pad = (image->xoffset + req_xoffset) & (dpy->bitmap_unit - 1);
	BytesPerRow = (ROUNDUP((long)req_width + left_pad,
			       dpy->bitmap_pad) >> 3) * image->depth;
    } else {
	left_pad = 0;
	BytesPerRow = ROUNDUP((long)req_width * dest_bits_per_pixel,
			      dest_scanline_pad) >> 3;
    }

    if ((BytesPerRow * req_height) <= Available) {
        PutImageRequest(dpy, d, gc, image, req_xoffset, req_yoffset, x, y, 
			req_width, req_height,
			dest_bits_per_pixel, dest_scanline_pad);
    } else if (req_height > 1) {
	int SubImageHeight = Available / BytesPerRow;

	if (SubImageHeight == 0)
	    SubImageHeight = 1;

	PutSubImage(dpy, d, gc, image, req_xoffset, req_yoffset, x, y, 
		    req_width, (unsigned int) SubImageHeight,
		    dest_bits_per_pixel, dest_scanline_pad);

	PutSubImage(dpy, d, gc, image, req_xoffset, 
		    req_yoffset + SubImageHeight, x, y + SubImageHeight,
		    req_width, req_height - SubImageHeight,
		    dest_bits_per_pixel, dest_scanline_pad);
    } else {
	int SubImageWidth = (((Available << 3) / dest_scanline_pad)
				* dest_scanline_pad) - left_pad;

	PutSubImage(dpy, d, gc, image, req_xoffset, req_yoffset, x, y, 
		    (unsigned int) SubImageWidth, 1,
		    dest_bits_per_pixel, dest_scanline_pad);

	PutSubImage(dpy, d, gc, image, req_xoffset + SubImageWidth, 
		    req_yoffset, x + SubImageWidth, y,
		    req_width - SubImageWidth, 1,
		    dest_bits_per_pixel, dest_scanline_pad);
    }
}

XPutImage (dpy, d, gc, image, req_xoffset, req_yoffset, x, y, req_width,
							      req_height)
    register Display *dpy;
    Drawable d;
    GC gc;
    register XImage *image;
    int x, y;
    unsigned int req_width, req_height;
    int req_xoffset, req_yoffset;

{
    long width = req_width;
    long height = req_height;
    int dest_bits_per_pixel, dest_scanline_pad;

    if (req_xoffset < 0) {
	width += req_xoffset;
	req_xoffset = 0;
    }
    if (req_yoffset < 0) {
	height += req_yoffset;
	req_yoffset = 0;
    }
    if ((req_xoffset + width) > image->width)
	width = image->width - req_xoffset;
    if ((req_yoffset + height) > image->height)
	height = image->height - req_yoffset;
    if ((width <= 0) || (height <= 0))
	return;

    if ((image->depth == 1) || (image->format != ZPixmap)) {
	dest_bits_per_pixel = 1;
	dest_scanline_pad = dpy->bitmap_pad;
    } else {
	register int n;
	register ScreenFormat *format;

	dest_bits_per_pixel = image->bits_per_pixel;
	dest_scanline_pad = image->bitmap_pad;
	for (n = dpy->nformats, format = dpy->pixmap_format; --n >= 0; format++)
	    if (format->depth == image->depth) {
		dest_bits_per_pixel = format->bits_per_pixel;
		dest_scanline_pad = format->scanline_pad;
	    }
	if (dest_bits_per_pixel != image->bits_per_pixel) {
	    XImage img;
	    register long i, j;
	    /* XXX slow, but works */
	    img.width = width;
	    img.height = height;
	    img.xoffset = 0;
	    img.format = ZPixmap;
	    img.byte_order = dpy->byte_order;
	    img.bitmap_pad = dest_scanline_pad;
	    img.depth = image->depth;
	    img.bits_per_pixel = dest_bits_per_pixel;
	    img.bytes_per_line = ROUNDUP((dest_bits_per_pixel * width),
					 dest_scanline_pad) >> 3;
	    img.data = Xmalloc((unsigned) (img.bytes_per_line * height));
	    if (img.data == NULL)
		return;
	    _XInitImageFuncPtrs(&img);
	    for (j = height; --j >= 0; )
		for (i = width; --i >= 0; )
		    XPutPixel(&img, i, j, XGetPixel(image, req_xoffset + i,
						    req_yoffset + j));
	    LockDisplay(dpy);
	    FlushGC(dpy, gc);
	    PutSubImage(dpy, d, gc, &img, 0, 0, x, y,
			(unsigned int) width, (unsigned int) height,
			dest_bits_per_pixel, dest_scanline_pad);
	    UnlockDisplay(dpy);
	    SyncHandle();
	    Xfree(img.data);
	    return;
	}
    }

    LockDisplay(dpy);
    FlushGC(dpy, gc);

    PutSubImage(dpy, d, gc, image, req_xoffset, req_yoffset, x, y,
		(unsigned int) width, (unsigned int) height,
		dest_bits_per_pixel, dest_scanline_pad);

    UnlockDisplay(dpy);
    SyncHandle();
}